I operate my air conditioning different than everybody else. I'm looking for the best way to keep the humidity/dew point low in the house where it is comfortable but I don't really have a goal of 72 degrees as I'm more comfortable with heat than most people as long as its not very humid in the house at the same time.
What I've been doing is early in the morning before it gets hot out(but not when its too cold for the a/c to run), I will run the air conditioning for 2 hours and shut it off. Then later on in the day when it gets hot, there is less humidity in the house and it doesn't feel warm. If it gets hot or humid in the house again during the day, I'll run it another two hours right before going to sleep so the house is comfortable.
I've done a fair amount of sun reduction through growing deciduous trees in the south and west sides of the house and also installed a few layers of bug screens to the sunnier picture windows to reduce the heat from the sun, it's working very well.
When I run the a/c for two hours in the evening on an 88 degree day where the inside got to 80 degrees, it will drop the temperature to 76 and the humidity to 34% (dew point 46), the basement is 62 degrees and 58% humidity in the same condition. The basement isn't finished and no ductwork to it(not looking to have any due to radon concerns) but it isn't isolated from the rest of the house in any way.
The equipment is a Carrier 58GS that had a blower motor die last fall and the tech retrofitted it with a PSC motor that consumes less power, he measured the ductwork and used his equipment on the returns and supply vents and says that its putting out 800CFM set to its highest speed tap with a new filter installed. The condenser is a Janitrol with a H21B223ABCA Bristol compressor which my tech says is a 23k compressor and the unit's nameplates are weathered and completely white but he spent the time to do a reverse look up and says he is 90% sure it is a Janitrol 24CL-1AB 8.5 SEER unit. His inspection with poking thermometers in places and measuring pressures and airflow is that the unit already has a proper charge and doesn't need any adjustment.
I showed him my electric bills and told him how I use air conditioning and he said that it wouldn't make any sense, financially to replace the unit unless the furnace cracks(he checked and its not) or if there was some other expensive repair. So far everything is fine except for the blower motor replacement which wasn't that much. He measured current draw, it is pulling 10 amps when it was 80 degrees out and he said that seemed normal to him.
When I run the unit for many hours, the humidity is mostly sapped from the air after 1.5 hours and anything longer than that and it seems the temperature drops slowly and the humidity stays steady. The tech said that when the unit shuts off that the coils moisture goes back into the house and that if I went with a 16SEER or higher unit that it would take more time to start removing the humidity and once I shut it off, it would be more humidity that gets added back. He also said the coil itself wouldn't be as cold and the humidity removal less effective for the amount of power used unless I wanted to drop the temperature to the same 72 degrees most people set their house to. This all makes sense but my question is, is 2 hours the right amount of time to gather and remove most of the easily removable latent heat from the air? Should I run it 3 hours or is 2 plenty? I'm really just trying to effectively remove the most humidity from the air as I feel comfortable in the house as long as it doesn't feel muggy.
House is 2200 sq ft total and the zip code is 55369.
What do you guys think, is 2 hours about the time it takes to remove the bulk of the humidity in the air? Thanks in advance.